On Jan 17, 2014, at 6:06 AM, James Hogarth <james.hogarth(a)gmail.com> wrote:
So far as I understand it when in the same pool cross-subvolume COW should be valid (as
shown in /data on the server) - even if technically under separate mounts.
I haven't yet found anything newer than this:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id...
The clone can be in different subvolumes but the source and destination must be the same
mount point.
There's a similar effect with btrfs send that might be related, and it has patches
upstream.
http://www.spinics.net/lists/linux-btrfs/msg30852.html
Chris Murphy